HIV-1 and HIV-2. Human Immunodeficiency Virus презентация

What is HIV?
Human
Immunodeficiency
Virus
“HIV is a virus spread through body fluids that affects specific cells of the immune system, called CD4 cells, or T cells”.
HIV kills the body’s CD4 cells
(T cells) and damages the immune system.
HIV replicates inside the human body. It must invade a healthy cell in the body to survive.
There is NO cure, but there is treatment.

What is AIDS?
AIDS is a late stage of the HIV infection
Once diagnosed, body has hard time fighting disease and certain cancers.
NO cure for AIDS, but there is treatment
Positive HIV Test
+
Very low CD4 count (<200 cells)
OR
presence of specific cancers or infections
=
AIDS
Diagnosis

HIV-1 and HIV-2
• HIV-1 and HIV-2 are
• Transmitted through the same routes
• Associated with similar opportunistic infections
• HIV-1 is more common worldwide
• HIV-2 is found in West Africa, Mozambique, and Angola

HIV-1 and HIV-2
HIV-2 is less easily transmitted
HIV-2 is less pathogenic
Duration of HIV-2 infection is shorter
MTCT is relatively rare with HIV-2

Life Cycle
(a) HIV (red) attaches to two cell-surface receptors (the CD4 antigen and a specific chemokine receptor).
(b) The virus and cell membrane fuse, and the virion core enters the cell.
(c) The viral RNA and core proteins are released from the virion core and are then actively transported to the nucleus.
(d) The viral RNA genome is converted into double-stranded DNA through an enzyme unique to viruses, reverse transcriptase (red dot).
(e) The double-stranded viral DNA moves into the cell nucleus.
(f) Using a unique viral enzyme called integrase, the viral DNA is integrated into the cellular DNA.
(g) Viral RNA is synthesized by the cellular enzyme RNA polymerase II using integrated viral DNA as a template. Two types of RNA transcripts shorter spliced RNA (h) and full-length genomic RNA (j) are produced.
(h) Shorter spliced RNAs are transported to the cytoplasm and used for the production of several viral proteins that are then modified in the Golgi apparatus of the cell (i).
(j) Full-length genomic RNAs are transported to the cytoplasm (k).
(l) New virion is assembled and then buds off.
(m) Mature virus is released.

How is HIV Spread?
HIV is passed from person to person through the exchange of bodily fluids.
3 Main Ways:
Unprotected sex with people living with HIV (vaginal, oral, or anal)
Blood to blood contact
Exposure to HIV before or during birth or through breastfeeding

What Fluids Can Transmit HIV?
Blood
Vaginal fluids
Semen
Breast Milk
8

HIV can enter the body through:
-Mouth -Vagina
-Nose -Penis
-Eyes -Anus
-Ears -Break in Skin

Transmission

HIV Disease
Direct infection of organ systems:
HIV can directly infect the;
Brain (HIV dementia)
Gut (wasting)
Heart (cardiomyopathy)

Primary HIV Syndrome
Mononucleosis-like, cold or flu-like symptoms may occur 6 to 12 weeks after infection.
lymphadenopathy
fever
rash
headache
Fatigue
diarrhea
sore throat
neurologic manifestations.
no symptoms may be present

Symptoms of HIV
-Many people who are infected with HIV have NO symptoms at all for 10 years or more.
-Currently 300,000-500,000 in U.S. have HIV and do not know it.
-Symptoms vary.
Some people who are infected with HIV report having flu-like symptoms 2-4 weeks after exposure.
Fever
Enlarged lymph nodes
Sore throat
Rash

The period of time after you may have been exposed to HIV, but before a test can detect it (at least 3 months)13
Antibody tests cannot accurately identify infection during this time.
Immediately contagious
WINDOW PERIOD
Incubation period-
Time from exposure to HIV to time when antibodies can be detected through an HIV test.

HIV antibodies present
Infected and can infect others
Need to begin treatment
No HIV antibodies detected
May not be infected (consider the window period)
Consider retesting
What
Does the HIV Test Mean?
Positive
+
Negative
-

The presence of an STD increases the possibility of:
acquiring infection with HIV
&
transmitting HIV
Why?
Compromised immune system
Infection from STD
Irritation and inflammation of mucous membranes
&

HIV Testing
CDC recommends routine HIV testing for ALL patients:
Aged 13-64
Initiating TB treatment
Seeking treatment for STI’s
Who are pregnant
Repeat Screening Recommended
Annually people at high risk
Before beginning a new sexual relationship
When clinically indicated
After an occupational exposure

Reducing your risk of HIV
No Risk —
Abstinence (sex): not having oral, vaginal or anal sex
Abstinence (drugs): not using drugs
Mutual monogamy between non-infected partners
Reduced Risk —
Protected Sex: “Correct and consistent” use of condoms/barriers16
Fewer sexual partners
Never sharing needles/”works”17
Regular HIV/STD testing18

Male Condoms
More than 98% effective when used correctly and consistently
Different kinds:19
Latex
Polyurethane (“Non-Latex”)
Lambskin

Do’s and Don’ts of male condom use21
Do’s
DO keep condoms in a cool, dry place
DO put the condom on an erect (hard) penis before any genital contact
DO hold the condom in place at the base of the penis before withdrawing (pulling out) after sex
DO throw the condom away after it’s been used
DO use water-based lubrication (vaginal sex) or silicone-based (anal sex)
Don’ts
DON’T use expired condoms.
DON’T unroll the condom before putting it on the penis
DON’T leave condoms in hot places (wallet, car, etc.)
DON’T use oil-based products (baby or cooking oils, hand lotion, Vaseline, etc.) as lubricants with latex condoms
DON’T use your fingernails or teeth while opening the condom wrapper.
DON’T reuse a condom
DON’T use more than one condom at a time

Female Condoms
Worn inside the vagina or anus
Thicker, more tear-resistant
Always latex-free
Wider opening covers more pelvic area
Dental Dams
Used for oral sex
Could make your own dental dam
More Protection

World Health Organisation (WHO) has recommended a combination of antiretroviral drugs for people starting HIV treatment:
TDF (tenofovir)
3TC (lamivudine) or FTC (emtricitabine)
EFV (efavirenz)
Drugs of HIV

Diagnosis of HIV
Antibody test
These tests check for a kind of protein that your body makes in response to the HIV infection, 2-8 weeks later. They're also called immunoassay or ELISA tests. They're generally very accurate, but they won't catch early infections.
Usually, a technician will take a small blood sample and send it to a lab for testing. Some immunoassay tests check urine or fluids from your mouth (not saliva), but there aren't as many antibodies in these, so you may not get a positive result even if you're infected. (That's called a false negative.)
Rapid versions of these blood and oral fluid tests can give results in under 30 minutes, but they may give false negatives, too.

Antibody antigen test
The CDC recommends these blood tests.
They can detect HIV as soon as 20 days earlier than antibody screening tests.They check for HIV antigen, a protein called p24 that's part of the virus that shows up 2-4 weeks after infection, as well as HIV antibodies.
A rapid antibody/antigen test can give you results in 20 minutes.
RNA/DNA test
This looks for the virus itself and can diagnose HIV about 10 days after you've been exposed. It's expensive, though, so it's usually not the first test. But if you're at high risk and you have flu-like symptoms, your doctor may want to use it.

Treatment does extend the lives of many people living with HIV, however….
Medication can be:
Expensive - $30,000 a year
$379,668 (lifetime)
Complicated –Different pills at specific times of the day
Toxic – side effects are common
Ineffective – not all strains of HIV respond